This is a new Verison of the Technology Depth Tree from Priax, which can be found under http://www.ti3wiki.org/images/7/75/Tech_Depth_Table.PNG
It includes all Techs and Races from Shards of the Throne and Shattered Empire except of the Nekro Virus (because they don't have to follow the Tree).
The Number shows how often a player has to acquire new Techs, to get the desired one. A Tech with 0 is a starting Technology. Example can be found in the original table (Link above)
You can find the image under: http://boardgamegeek.com/image/1226846/twilight-imperium-thi...
Excuse my bad English(if it is bad, i don't know)!